Electric switch



June 25, 1929. H. TRENCHAM a AL ELECTRIC SWITCH Filed Sept. 1925 2 SheetsSheef.

Inventors-31 Q 7n $0 hum n C r nH w e .Ni 2W m Tn; n a% e e C HH {929- H. TRENCHAM firm; 1. 1 .501.

n ELECTRIC swz'rcn Filed Sept. 8, 192's 24 x' I 48 a o ,7 Inventors.

Her-15y Trencham, Herbert C. Heath, Caleb W Newton,

by, TheirAItornegy.

' 2 Sheets-Sheet 2 Patented June 25, 1929.

UNITED STATES PAT ENT OFFICE.

HENRY TRENGHAJE, OIJRUILIP, -HERBERT' c. HEATH, or 'WEMBLEY, AND CALEB w. NEWTON, or HARLESDEN, LONDO ENGLAND, ASSIGNORS T0 GENERAL ELEo- TRIO COMPANY, A .ooRroRA'rIoN on NEW YORK.

ELEo'r Io SWITCH.

Application'filed September '8, 1925, .Se'riai No. 55,188, and in Great Britain September 30, 1924.

Our invention relates to electric switches, particularly to switches of the type known as iron-clad wherein a number of units may be arranged side by side, each unit comprising a circuitbreaker, usually an oil circuit breaker, one or more bus bar chambers, one or more feeder chambers, and one or more isolating devices or switches for each circuit.

One object of our invention is the provision of improved means for causing the terminals of the breaker properly to engage and be disengaged from the terminals of the desired bus bar and feeder chambers. Another object of our'invention is the provision of-improved means for automatically covering and uncovering the terminal of the bus bar and feeder chambers in accordance with the position of the breaker Our invention will be better understood from the following description taken in connection with the accompanying drawing, and

its scope will be pointed out in the appended claims. a In the drawing, Figure 1 1s a side view of a switch involving our invention, Figure 2 is an end view of the same and Figures 3 and 4 are details a According to thearrangement illustrated, the switch consists of a frame 11 arranged at the top of which are three parallel chambers 12,13 and 14, the center one 13 carrying the feeder terminals and the two outside chambers 12 and 14 carrying bus bars 15 and 16 with their respective terminals. These terminals are preferably socket terminals, there being three for each chamber, i. e., one for each phase. The three phase circuit breaker 17 is mounted 011 a horizon al structure 18. preferably a track, along which it is adapted to move, rollers 19 beingprovided whereby it can be supported. The supporting structure 18 may be lifted or lowered through the agency of a number ofnuts 21 fixed to it, preferably at its four corners, co-

- operating with an'equal number of verticallyarranged lifting screws 22, which screws may be geared together in any suitable way, as for example by means of a chain 23 and bevel gearing 24 so that upon operation of a handle or handles 25 all the screws revolve in the same direction at the same rate to raise or lower the structure uniformly, whilst keeping it in a horizontal plane. Whenin its operative lower position as indicated by the dot and dash lines 20, the main outside terminals of the circuit breaker, which are of the plug type and carried by the bushings 26, are withdrawn from the corresponding socket terminals in the feeder 13 and whichever bus bar chamber was previously connected. In this position the circuit breaker can be moved horizontally on its track18 to adopt a position from which when raised sufliciently it will interconnect the feeder chamber 13 with the other bus bar chamber through its external plug contacts. The plug contacts on thecircuit breaker and the socket contacts in the bus bar and feeder chambers, it should be noted, constitute isolating devices. With this arrangement, it will be readily understood that horizontal movement of the circuit breaker is prevented except when the same has been lowered a predetermined amountin order that its plug contacts may be clear of the cooperating socket contacts.

Gravity-controlled shutters 27, 28 and 29 are shown arranged to close the lower ends of the bus bar and feeder chambers when the circuit breaker structure is lowered sufiicient- I ly, and any suitable operating mechanism therefor may be provided whereby, when the circuit breaker is raised in order to close the isolating contacts in the circuit of the feeder chamber and one of thebus bar chambers. only-the shutters covering these two chambers will be operated to uncover them In order to ensure that, when the circuit breaker is raised to close these isolating contacts, it is in its correct horizontal position,

a number of dowel pins cooperating with suitable guideways are arranged to guide the same during its upward movement or to prevent the upward moveme'nt thereof when the same is not in correct alignment. In the arrangement illustrated, the dowel pins 31 are secured to the circuit breaker by brackets 32, pointing upwards in the vertical plane through the middle thereof. and are arranged, when the breaker is in its correct horizontal position, to pass between pairs of cooperating rollers 33 arranged. respectively, in the vertical planes between the feeder chamher and the bus bar chambers.

The dowel pins are arranged to operate the shutter-operating mechanism aforesaid, such mechanism comprising rods 34 connected to the feeder chamber shutter 28 above and on each side of the pivot 35 thereof and also to I mechanism to rotate shutter-28 up between the feeder chamber 13 and the back bus bar chamrocking levers 36, pivoted 37. The ends of these levers normally lie Just above the pairs of rollers 33, respectively, and are adaptedto,

Withthis arrangement when the circuit breakeris in a position, say,-f ron1 whichthe front bus bar chamber 12 can be connected'jco the feeder chamber 13, as illustrated, upward movement of the breakerloperates the shutter ber 14. The shutter 28 is shown connected to the bus bar chamber shutters 27 and 29 means of pins 38 working in slots39 in the con.-

' necting rods 41 in such a way that'shutter 27 is directly operated whilethe pin rides idly in the slot ofthe connecting rod of the back bus bar chamber shutter 29 withoutoperating it.

. In a similar manner, when the breaker isin a position from which the back bus bar chamber 14 m y be interconnected withthe'feeder shutter 28 inthe opposite direction ie., between feeder chamber andthe front bus bar chamber 12, operates the 'Sllfitlff290fth6 chamber 13, upward movement of thebreaker effects the rotationofthe feeder chamber back bus bar chamber directly, while the pin. runs idly in'the' slot-of the connecting rodnf shutter-27without operatingthe same.- For mechanical reasons, similar shutter-operating mechanisms are preferably arranged on each side of the-st-ructure. w

Any suitable arrangement may be provided whereby the'circuit breaker platform 18 cannot be lowered when it is in its raised position withthe circuit breaker remaining "closed.

For instance, movement of the handle 25 which operates the lifting and lowering gear of the platform 18 may be-arranged to effect the tripping of the circuit breaker and topi-ejlvent the "reclosing thereof, except when the platform is'lowered, in which position it may bedesirablafor testing brother reasons, to

- open and close the circuit breaker. When lowered it willreadily be understood that the feeder circuit is not connected with earner the busbar circuits-due to the fact that the isolating devices are fully'open.

A suitable construction of interlock for this purpose is illustrated in Fig. 3,-comprising a notched cam 42 pivoted at 43 to thebreaker. The sliding lever 44 is connected to the-cam and the spring 45 biasesthe cam outwardly, in which position the inner end of the lever is ust clear of the tripping bridge of the tripping mechanism 46. As shown in Fig. 3 the 60.

circuit breaker is fully raised and the cam is n its outward position, the breaker thus being free to be closed or opened. When the movable structure 18 begins to be lowered,

the lower side 47 of the cam, riding upon the horizontal shaft 48 of the lowering and lifting gear, forces the cai n and sliding lever 44 inwardly, thus tripping the breaker before it has been appreciably lowered. The cam is so designed that the upper inclined portion 49- lies just below the shaft 48 when the breaker is lowered sufliciently for the isolating devices to be opened in vhich position, the breaker may be opened or'closed. Thus, when the movable platform is raisedfthe inclined surface 49 rides;against thershaftl48 and trips the breaker, while the isolating device is still open, if the breaker wereclosed. i

:for -efiecting this, in'accor'dance with anather As .it is sometimes-desirable to grbiindthe feeder circuit, improved means are providedfeature of our invention, This means comtions therein which connect the breaker with v the feeder. Those extensions on the other bushings of the breaker have conducting portion's which do not connect with the bus bars covered, but instead each has a connection to ground.- With the extensions 50 therefore properly-placed the breaker when in the "raisedposition may be used for thepurpose ofopening and closing a ground connection -to the feeder. Wd en' the breaker is fully raised, it will not be so high as in normal circumstances', due to the extensions50, and the notch 51 is provided in the tripping cain to permit the openin'gor closing of the breaker when. in its. grounding raised position. When the breaker is'closed the feeder circuit is, of course, grounded. f

Advantages of anarrangem'cnt according to our invention, as'previously described, are

when .the breaker israised, being insulation a positive interlock whereby. a feeder circuitcan only be connected to one of the bus bar circuits'atany given moment combined with certa n means of indicating which .bus bar isin use e., the horizontal position of thebreaker) considerable ease in changing over from one bus bar toanother; security against 1 coming in contact with the live terminal in the bus bar chambers; and economy of space as compared with the truck type of switch gear. Another advantage residcs in the fact that, when the breaker requ res examination or cleaning, the breaker may be lowered until its tank (or tanks) touchesthe ground orlVhat we claim as new and desire to secure by Letters Patent of the United States is r 1. An electric switch-comprising a plurality of bus bar terminals and an intermediate feeder terminal, a circuit breaker having terminals thereon and means for moving the circuit breaker bodily to cause its terminals to engage either the feeder terminal and one bus bar terminal or the feeder terminal and the other bus bar terminal.

2. An electric switch comprising downwardly facing bus bar and feeder terminals, a circuit breaker having terminals adapted to engage said terminals, a track'on which the circuit breaker is adapted to be moved horizontally and means for aising the track and the circuit breaker to cause the terminals of the breaker to engage the bus bar and feeder terminals.

3. An electric switch comprising a plurality of downwardly facing bus bar terminals and an intermediate feeder terminal, a track, a circuit breaker mounted to be moved horizontally thereon and having terminals and means for raising and lowering the track with the breaker whereby the breaker termianls may be brought into engagement either with the feeder terminal and one bus bar terminal or with the feeder terminal and the other bus bar terminal.

4. An electric switch comprising a plurality of uniformly spaced stationary terminals, a movable circuit breaker having a pair of fixed terminals, means for moving the breaker to selectively bring its terminals into engagement with different pairs of the stationary terminals, a shutter for each of the stationary terminals, and means responsive to movement of the circuit breaker toward a selected pair of stationary terminals for moving only the shutters of the selected pair of terminals.

5. An electric switch comprising a pair of bus bar terminals and a feeder terminal, a movable shutter for each terminal adapted in one position to cover its terminal, a circuit breaker having a pair of terminals and movable to a plurality of terminal connecting posilionsm'hereby in one position its terminals engage respectively the feeder terminal and one bus bar terminal and in another position engage the feeder terminal and the other bus bar terminal, and means responsive to the movement of the circuit. breaker to one or the other of said positions for moving the shutters of the corresponding terminals to uncovering position, the remaining shutter being maintained in terminal covering position.

6. An electric switch comprising a plurality of stationary terminals, a movable circuit breaker having terminals adap'ledto engage the stationary terminals, an attachment for the circuit breaker forming extensions of its terminals, certain of said eXtensi ns b eing insulation covered and connected together and a ground connection for said insulated extensions.

7. A metal clad selective electric switching equipment comprising a plurality of stationary terminals arranged 111'2tl1118111611l3, a c1rcuit breaker having terminals thereon adapt:

ed selectively to engage certain ones of the stationary terminals, a track on which the circuit breaker may be moved to bring it opposite the selected stationary terminals and means for moving the circuit breaker relative to the stationary terminals to cause engagement of the circuit breaker terminals -with the selected stationary terminals,

8. A metal clad selective electric switching equipment comprising a plurality of downwardly facing stationary terminals arranged in horizontal alinement, a circuit breaker having a pair of terminals adapted to engage various selected pairs of said stationary terminals, a track on which the circuit breaker is adapted to be moved horizontally and means for raising the'circuit breaker to cause its terminals to engage the selected pairs of the stationary terminals.

9. An electric switch comprising a plurality of bus bar terminals and a feeder terminal, a circuit breaker having cooperating terminals thereon and means for moving the circuit breaker relative to the bus bar and feeder terminals whereby the circuitbreaker terminals selectively engage the feeder terminal and one bus bar terminal or the feeder terminal and the other bus bar terminal.

10. A metal clad electric switching equip.

a plurality of stationary terminals arranged to form two pairs of equally spaced terminals, a circuit breaker having a pair of similarly spaced terminals and having a plurality of operating positions in the housing, and means for movably'mounting the circuit breaker in the housing, said breaker being adapted in one position to have its terminals connect with the stationary terminals forming one of said pairs and in another position to have its terminals connect with the stationary terminals forming the other of said pairs.

In witness whereof we have hereunto set our hands this 13th day of August, 1925.

HENRY THENCHAM. HERBERT C. HEATH. CALEB TIM. llEiV-TON. 

